Clos architectural features may be used to build large scale networks; i.e., a Clos network. A Clos network uses a multistage switching circuit. Clos networks are useful when the physical switching needs exceed the capacity of the largest feasible single crossbar switch. A further advantage of Clos networks is that the required number of crosspoints (which make up each crossbar switch) can be much fewer than were the entire switching system implemented with one large crossbar switch.